Abstract : Dynamic optical techniques (light emission and laser stimulation techniques) are routinely used for precise IC defect localization. As device technology is more and more shrinking, developing new techniques for defect localization is becoming a crucial challenge. Dynamic Laser Stimulation (DLS) techniques based on near-infrared laser scanning are used for failure analysis, design debug and time margin studies or critical path analysis. Using Time Resolved Emission (TRE) technique, scan chain, timing and logic failure are shown to be quickly and precisely identified [1]. On 180nm and 120 nm test structures devices, we will present results showing the accuracy and the complementary of DLS and TRE in order to help Failure Analysists or Debug engineers to localize defect without performing physical analysis.